Year Percent of total labor force 1983 3.85 1984 3.75 1985 3.65 1986 3.3 1987 3.071 1988 3.142 1989 3.141 1990 3.13 1991 5.85 1992 5.85 1993 4.73 1994 4.84 1995 5.37 1996 5.37 1997 6.12 1998 5.89 1999 5.89 2000 7.82 2001 7.82 2002 8.27 2003 8.27 2004 7.69 2005 7.69 2006 6.2 2007 5.2 2008 5.2 2009 5.46 2010 5.55 2011 5.95 2012 5.95 2013 5.975 2014 6 2015 5.9 2016 5.958 2017 6.018 2018 6.079 2019 6.14 2020 6.202 2021 6.265 2022 6.328 2023 6.392 2024 6.457